I have no idea how often but I do know that they had one on the Coral Princess about 2 weeks ago that was unannounced. Talking to the crew, they said that it's a random selection & one of the guys in the buffet had been on the ship for 2 contracts & had never been selected.
I suspect that might do a check of all new employees as soon as they join the ship.

I am about to join ship in 3 days and I smoked a joint a week ago, do they test new staff straight away?

Passing a drug screen for marijuana is something that's hard to predict. It really depends on how heavy and long you smoked. It also depends on your weight, BMI and the amount you smoked on your last use.

If it's a urine test and you are not a heavy smoker and have a normal BMI then it will take about 7 - 13 days to get out of your system. If it was a one time use then it will be out in less than 7. If you have been a regular smoker it can stay there for 90 days.

If it's a hair sample, then you will fail.

I'm not sure when they test on board. For my division, in the late '90s and early 2000's, I required drug screens for all new hires and screening if there was suspected usage.

Take care and definitely don't smoke during your contract.
Mike

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